1. Field of the Invention
The present invention relates to flexible printed circuit boards, and more particularly to a flexible printed circuit board which allows the order of arrangement of a plurality of conductive patterns on the side of one end thereof and that on the side of the other end thereof to arbitrarily differ from each other without causing the plurality of conductive patterns to cross each other midway in the patterns.
2. Description of the Related Art
Conventionally, as shown in FIG. 1, when a first printed circuit board 2 and a second printed circuit board 2' are to be connected to each other by means of a one-sided flexible circuit board 1, if the order of signal lines of a first flexible circuit board connector (hereinafter referred to as the FPC connector) 4 provided on the first printed circuit board 2 is different from the order of signal lines of a second FPC connector 4' provided on the second printed circuit board 2', as illustrated in FIG. 1 in which the former order is c-b-a (the characters a, b and c being the names of the signal lines) and the latter order is b-a-c, the following procedure is generally taken to rectify the disorder of the signal lines. Namely, as shown in FIG. 1, conductive patterns 1a and 1a' are provided to connect the signal lines a--a, while conductive patterns 1b and 1b' are provided to connect the signal lines b--b, and copper foil lands of the corresponding conductive patterns 1a and 1a' or 1b and 1b' are connected to each other by soldering by means of a plated jumper wire 3 or 3' in such a manner as to straddle a conductive pattern 1c for connecting the signal lines c--c.
With this method, however, there is the drawback that the number of work processes increases since, in order to rectify the disorder of the signal lines, it is necessary to solder plated jumper wires and attach an insulating tape to prevent the jumper wires from coming into contact with other parts such as electrodes and conductive patterns.
In addition, it is also possible to make use of the technique disclosed in Japanese Patent Publication No. Sho 59-30552 without providing any plated jumper wires separately. According to this technique, conductive patterns are cut and raised, as shown in FIG. 2, and tongue portions 1e and 1f of the cut and raised conductive patterns are used in place of the plated jumper wires.
However, even if such conductive patterns are used instead of the plated jumper wires, the number of work processes increases since the conductive patterns must be cut and raised, one end of each of the tongue portions 1e and 1f must be screwed down, and soldering must be carried out.